Circulating sleeve

ABSTRACT

In a drilling system, a subassembly provides a means for seating an instrument housing in the drill string during a drilling operation and for permitting a normal flow of drilling fluids around the instrument housing. The seat also provides means for orienting the instrument housing in a predetermined position relative to a portion of the drill system.

1451 Oct. 16, 1973 United States Patent 1191 Kielman, Jr.

l75/4.5l X Alberts 175/451 175/44 CIRCULATING SLEEVE 2,361,204 171323Howard etal.

[75] Inventor: Fred 3,450,216 6/1969 l-lugeletal.

[73] Assignee: Sperry-Sun WellSurveying Company, Sllgarland,T X- PrimaryExaminer-David H. Brown [22] Filed, Apr 21 1972 Attorney-George L.Church et a1.

Applv No.: 246,293

[57] ABSTRACT In a drilling system, a subassembly provides a means forseating an instrument housing in the drill strin during a drillingoperation and for permittin flowof drilling fluids around the instrume[52] US Cl 175/320, 175/45 [51] Int. E2lb l7/00 g a normal nt housing.

[58] Field oi Search...................... l75/4.5l, 44, 45, 175/73, 75,61, 320, 324

The seat also provides means for orienting the instr ment housing in apredetermined position relative to a [56] References cued portion of thedrill system.

UNITED STATES PATENTS 5 Claims, 3 Drawing Figures PATENIEnum 16 I975 3765 494 sum 1 OF 2 y In l \3 PATENTED OCT 16 I373 SHEET 2 OF 2 FIG. 2

BACKGROUND OF THE INVENTION The present invention pertains to acirculating sleeve and more particularly to an apparatus for orientingan instrument within a drill string and providing for the circulation offluid about the instrument tov permit drilling when an instrument isseated therein.

When drilling boreholes in the earths surface it is often desirable forvarious reasons to deviate the holes from a vertical course through theearth formations. The term directional drilling is applied to suchoperations. One example of the use of such directional drillingoperations is found in the drilling of oil wells from offshoreplatforms. It is a common practice to build large drilling platformswhich are permanently secured to the ocean floor and from which amultiplicity of wells are drilled. Because of the number of wells whichare drilled from a single platform, it is necessary to drill the holeslaterally away from the platform so that earth formations containingpetroleum reservoirs may be penetrated at distances laterally spacedfrom the platform. This procedure permits production from as great anarea as possible from a single platform. It is easily understood howimportant the maintenance of direction and dip of such boreholes is inorder to penetrate particular formations at predetermined depths andthereby intersect the desired petroleum reservoirs.

One technique for obtaining such information as to the direction of aborehole is to cease drilling and run a surveying instrument into thedrill pipe on a wire line. Alternatively, the instrument may bego-deviled to the bottom of the drill pipe. The instrument is orientedwith respect to the drill stem by means of a muleshoe sub located at thelower end of the drill stem. The muleshoe" is simply a device forcapturing the tool and orienting the tool in a predetermined radialdirection with respect to a position on the drill ste'm. For example,the drill stem normally used in such'a directional drilling operationincludes what is normally termed a bent sub," at its lower end whichplaces a bend in the lower end of the stem and thereby permits angulardeviation of the drill bit. The muleshoe" is normally oriented withrespect to the bent sub. This in turn orients the instrument which isbeing positioned in the lower end of the drill stem. This series oforientation procedures provides a correlation between the direction inwhich the drill bit is angled and the directional alignment of thesurvey instrument. After the survey instrument is operated to generate arecord, generally be means of a timing mechanism, the tool is retrievedto the surface by means of a wire line. The record is then processed andexamined to determine the direction in which the hole is being drilled.a

More recently, techniques have been developed f passing an instrumentinto the drill stern by means of a conductor cable to provide continuousdirectional information to the surface during the drilling operation.This technique also utilizes the method described above of locating theinstrument within a muleshoe which in turn is oriented in a particularradial direction with respect to a bent sub" in the drill string. Thus,the information which is received at the surface indicative of thedirection in which the survey instrument is positioned is correlatedwith the direction that the bit is angled.

It is common in such directional drilling operations to use a mud motoror turbine for rotating the drill within the borehole. Such a motor orturbine requires the continuous circulation of drilling fluidsthroughthe motor to provide the power for turning the drill. Therefore, it isessential that a constant flow of drilling fluids be maintained throughthe system even while an instrument is positioned within the drill stem.

It is therefore an object of the present invention to provide a new andimproved circulating sub for receiving an orientation instrument withina drill string.

SUMMARY OF THE INVENTION With this and other objects in view, thepresent invention contemplates a drill pipe having a recessed portiontherein forming a seat within the bore of the pipe. A sleeve which issized for reception within the recessed portion has a shoulder whichwhen received within the recess mates with the seat. A plurality ofIongitudinal ribs are formed on the sleeve and extend upwardly from theshoulder. Means extend inwardly from the sleeve for engaging a matingsurface on an instrument housing to thereby locate the instrument in apredetermined manner within the sleeve.

BRIEF DESCRIPTION OF THE DRAWINGS DESCRIPTION OF THE PREFERREDEMBODIMENTS Referring first to FIG. 1 of the drawings, the lower end ofthe'drill stem is shown including a drill collar 27 and a muleshoeorienting sub 28. A bent sub 29, mud motor'or turbine 31, and a rotatingbit sub 32 are positioned below the orienting sub. An instrument whichfor the purpose of this disclosure shall be referred to as an orientingtool 33, is shown positioned within the interior bore of the drillcollar and is connected at its upper end with a conductor cable 26extending to the surface. Typically, the conductor cable would extendthrough a line wiper at the surface and be taken up on a motor drivendrum which permits its playout and take up during operations. The linewiper is constructed to seal off well pressure at the wellhead duringline operations in the drill pipe.

Referring again to the lower end of the drill stern, a

muleshoe sleeve 34 is shown positioned within the muleshoe orienting sub28 and is oriented therein in a predetermined fashion. The sleeve 34 isheld in the predetermined position within the sub by means of a screw orthe like 36 extending through the side wall of the sub 28. The muleshoesleeve 34 is shown having a key 37 positionedin its sidewall andextending inwardly into the sleeve bore. The muleshoe and its key arenormally oriented directionally with respect to the bent sub and thuswith respect to the drill bit which derives its direction of inclinationby means of the bent sub. This predetermined alignment of the muleshoekey with respect to the bent sub is convenient for purposes ofdetermining the original orientation of the drill with respect tosurface indications of tool direction and thereafter for makingcompensating changes in drilling direction. The muleshoe sleeve orcirculating sleeve as it will be hereinafter referred to, may beutilized to positionally locate various types of instruments within adrill 'pipe; however, since one of its primary uses is for locatingdirectional drilling orienting instruments this disclosure will continueto use such an instrument as an example.

The orienting tool 33 which is shown schematically in FIG. 1 includes amuleshoe 39 which is secured to the lower end of the tool string. Themuleshoe includes a protruding shaft or stinger 41 having a tapered end42 (see FIG. 2) for guiding the stinger into the muleshoe sleeve 34. Ashoulder 43 extends spirally around'opposite sides of the stinger,meeting at a pointed terminus 44, to form a camming surface. On theopposite side of the tool from the terminus 44, the spiral shoulders 43meet to form a short longitudinally extending slot 45. The slot 45 issized to receive the inwardly extending key 37 on the muleshoe sleeve 34when the tool 33 is positioned in the drill pipe. The tool string 33further includes a muleshoe adjuster which permits rotation of themuleshoe 39 relative to the tool string 33. The adjuster includesincludes mating portions (not shown) between the muleshoe and toolstring to permit relative rotation therebetween, and a locking collar 35for securing the tool string and muleshoe in a fixed rotationalposition. Greater detail of the muleshoe and its functional use with anorienting tool is shown in co-pending U.S. Pat. application Ser. No.86,877, now U.S. Pat. No. 3,7l8,l94, which is assigned to same assignoras the present application.

Referring next to FIG. 2 of the drawings, the circulating sleeve 34 andits cooperative relationship with the sub 28 is shown in greater detail.Sub 28 has a recessed bore portion 46 with a tapered seat 47 at itslower end. The circulating sleeve 34 is shown positioned within the sub28. The sleeve 34 has a body portion 49 with longitudinal ribs 48extending outwardly therefrom into contact with the recessed inner boreportion 46 of the sub 28. The longitudinal ribs 48 extend downwardlybelow the lower end of the body portion 49. A cylindrical sleeve 51 isformed at the bottom end of the longitudinal ribs. Tapered top andbottom surfaces 52 and 53, respectively, are formed on the sleeve 51.The lower surface 53 is arranged to matingly seat on the tapered surface47 of the recessed bore 46 in sub 28. Upper and lower peripheral grooves54 and 56, respectively, are formed on the surface of the exterior wallof sleeve 51, and are sized to receive O-ring seals therein. Anotherperipheral groove 57 is formed between the grooves 54 and 56 in theouter wall of the sleeve 51 for receiving an inwardly extending endportion of a set screw 36. The body portion 49 of the circulating sleeve34 and one of the longitudinal ribs 48 have an'aligned opening formedthrough the rib and body portion for receiving the key 37. The key 37has an enlarged shoulder portion 61 formed thereon which abuts acomplimentary shoulder formed in the rib opening.

In the operation of the system described herein the following method isemployed: the circulating sleeve 34 is inserted into the upper end ofsub 28 until the lower tapered surface 53 on sleeve 51 is matinglyseated on tapered surface 47 within the bore of sub 28. The circulatingsleeve is then rotated within the bore of sub 28 until the key 37 whichextends inwardly from the sleeve is positioned in accordance with apredetermined arrangement to permit orientation with respect to aportion of the drill stem. Normally, the predetermined alignment of thekey 37 is in some relationship with the bent sub 29 so that it is knownthat the muleshoe key 37 is pointing in a particular direction withrespect to that in which the drill is pointing. This arrangementprovides means for determining, by means of an orienting instrument tobe located within the muleshoe sub in what direction the drillingoperation is being conducted. In any event, after the key 37 and thecirculating sub has been oriented within the sub 28, set screws 36 arerotated until they extend inwardly into the groove 57 on lower sleeve 51and tightened therein to hole the sleeve in a fixed relationship withthe sub 28 and thereby prevent its rotation within the sub. Next, thesub 28 is made up in the drill string and the drill string is loweredinto the wellbore for purposes of performing the drilling operation.

Thereafter, when it is desired to lower an instrument into the drillstem by means of the cable 26 shown in FIG. 1, such instrument islowered until the muleshoe stinger 41 extends into the circulating sub34 whereupon the spiral camming surface 43 thereon engages the key 37and produces a camming action to rotate the muleshoe until thelongitudinal slot 45 of the muleshoe drips over the key 37. Theprocedure thus far described permits the instrument housing locatedabove the muleshoe to be radially positioned within the drill stem in apredetermined manner. The arrangement of the circulating sub, seat andmuleshoe permits the circulation of drilling fluids through the drillstem even when the instrument and muleshoe are seated within the drillstring. This is provided by means of the annular spaces between thelongitudinal ribs 48 and between the sleeve 51 and the lower end of themuleshoe. The path of such fluid circulation is shown by the arrows inFIG. 2.

With the circulating sub described herein the volume of fluid that maybe circulated through the system is sufficient to drive the mud motor orturbine during drilling operations while permitting the continuous useof an orienting instrument.

Wile a particular embodiment of the present invention has been shown anddescribed, it is apparent that changes and modifications may be madewithout departing from this invention in its broader aspects andtherefore the aim in the appended claims is to cover all such changesand modifications as which fall within the true spirit and scope of thisinvention.

What is claimed is:

1. In a drilling system utilizing a hollow conduit for carrying adrilling fluid means for seating an instrument housing within theconduit while performing a drilling operation, which means includes: aseat formed within the bore of said conduit, a sleeve sized forreception within the bore of said conduit, shoulder means on one endof-said sleeve for providing a mating reception of said sleeve withinsaid seat, said shoulder means being sized for close fitting receptionwithin said conduit, a plurality of longitudinal ribs on said sleeveextending above said shoulder means and key means extending inwardlyfrom said sleeve for orienting an instrument housing.

2. The apparatus of claim 1 and further including a transverse openingextending through one of said ribs and sleeve for receiving said keymeans.

3. The apparatus of claim 1 and further including means of locking saidsleeve against relative movement with said conduit.

4. The apparatus of claim 3 wherein said locking means extends throughthe wall of said conduit and further including seal means on saidshoulder arranged to be positioned above and below said locking meanswhen said sleeve is seated in said conduit.

5. A circulating sleeve for seating and orienting an instrument housingwithin the bore of a drill pipe during a drilling operation and arrangedto permit the flow of fluids through the drill pipe when an instrumenthousing is positioned therein, comprising: a sleeve for reception withinthe bore of the pipe, and having a cylindrical portion with longitudinalribs formed thereon for engaging the bore of the pipe and maintain saidcylindrical portion in a spaced position from said bore; a shoulderformed on said sleeve for engaging a seat in the pipe; key meansextending from the wall of said cylindrical portion into its bore forengaging a portion of the instrument housing to orient the housing withrespect to said sleeve; and means on said sleeve for receiving a memberextending from the wall of the pipe for holding said sleeve againstrotation relative to the pipe.

1. In a drilling system utilizing a hollow conduit for carrying adrilling fluid means for seating an instrument housing within theconduit while performing a drilling operation, which means includes: aseat formed within the bore of said conduit, a sleeve sized forreception within the bore of said conduit, shoulder means on one end ofsaid sleeve for providing a mating reception of said sleeve within saidseat, said shoulder means being sized for close fitting reception withinsaid conduit, a plurality of longitudinal ribs on said sleeve extendingabove said shoulder means and key means extending inwardly from saidsleeve for orienting an instrument housing.
 2. The apparatus of claim 1and further including a transverse opening extending through one of saidribs and sleeve for receiving said key means.
 3. The apparatus of claim1 and further including means of locking said sleeve against relativemovement with said conduit.
 4. The apparatus of claim 3 wherein saidlocking means extends through the wall of said conduit and furtherincluding seal means on said shoulder arranged to be positioned aboveand below said locking means when said sleeve is seated in said conduit.5. A circulating sleeve for seating and orienting an instrument housingwithin the bore of a drill pipe during a drilling operation and arrangedto permit the flow of fluids through the drill pipe when an instrumenthousing is positioned therein, comprising: a sleeve for reception withinthe bore of the pipe, and having a cylindrical portion with longitudinalribs formed thereon for engaging the bore of the pipe and maintain saidcylindrical portion in a spaced position from said bore; a shoulderformed on said sleeve for engaging a seat in the pipe; key meansextending from the wall of said cylindrical portion into its bore forengaging a portion of the instrument housing to orient the housing withrespect to said sleeve; and means on said sleeve for receiving a memberextending from the wall of the pipe for holding said sleeve againstrotation relative to the pipe.